Piezoelectric actuators using a piezoelectric element, such as the one described in Patent Literature 1 below, have heretofore been proposed as small-sized actuators for use in camera autofocus mechanisms, for example. FIG. 13 is a schematic perspective view of a piezoelectric actuator described in Patent Literature 1. As shown in FIG. 13, the piezoelectric actuator 100 includes a piezoelectric ceramic part 101 and non-piezoelectric ceramic parts 102 and 103 connected to both ends of the piezoelectric ceramic part 101. The piezoelectric ceramic part 101 is internally provided with a plurality of pairs of opposing first and second internal electrodes 104 and 105. The first internal electrodes 104 are connected to a first external electrode 106 formed on the outside surface of the piezoelectric ceramic part 101. On the other hand, the second internal electrodes 105 are connected to a second external electrode (not shown) formed on the outside surface of the piezoelectric ceramic part 101. Each of the first external electrode 106 and the second external electrode is connected to an external lead 107 by a solder 108.
In the piezoelectric actuator 100, voltage is applied between each pair of first and second internal electrodes 104 and 105 via the external leads 107, the solders 108, the first external electrode 106, and the second external electrode. Thus, the piezoelectric ceramic part 101 expands and contracts. As a result, the piezoelectric actuator 100 is driven.
Patent Literature 1 describes that in assembling this piezoelectric actuator 100 into a machining apparatus or the like, both ends thereof existing in the non-piezoelectric ceramic parts 102 and 103 are fixed, by an epoxy adhesive, one end to a support member and the other end to a driven member.
Patent Literature 1: Japanese Registered Utility Model No. 2587406